Sunday, 20 April 2014

Breaking the law of averages... statistically speaking

Well, this is a surprise – though I suppose it was always likely to
happen one day. I’ve been invited by the Royal Statistical Society to enter for
its Awards for Statistical Excellence in Journalism.

To be honest – a quality
not always evident in the use of statistics – I didn’t know the awards existed.
Or indeed the society, though I might have guessed such a thing was probable.

I’m flattered, of
course, to be asked. My selection may, for all I know, be a matter of random
chance, but as far as I’m aware none of my journalist friends has been invited.

So it seems a fair
probability somebody at the august society has noticed that this column is a
friend of statistics, used clearly and properly. And, even more, an enemy of
statistics used improperly.

Too often they are
used as a weapon to “blind people with science” – a tactic, much beloved of
governments, which has a lot to do with blinding and stuff all to do with
science.

Or just sloppily
used by people who don’t know their statistical coccyx from their arithmetical
humerus.

Statistics are
incredibly useful, in many different ways. But they can also be incredibly
misleading in the hands of people who don’t understand them – or who are
banking on the likelihood that you don’t.

Opinion
polls are one vastly over-used source of statistics, often mis-used, and
frequently all but meaningless. Nevertheless, the following is rather
illuminating.

What
proportion of the national welfare budget do you think is spent on the
unemployed?

According
to a YouGov poll, people on average believe the figure is 41 per cent. In fact
it’s 3pc.

And how
much of it is fraudulently claimed by “scroungers”?

The
popular belief averages out at 27pc. The reality is 0.7pc.

Why are
so many people so wrong about these things? Because right-wing politicians, and
their stooges in the media, have done such a good job over so many years of
persuading us.

It’s a
win-win tactic for them. By bringing the welfare state into disrepute they make
it easier to dismantle it.

And by
turning working people against each other they draw the flak away from
themselves. It’s divide and rule in practice.

And
here’s another statistic that says a lot about the degenerate state of British
democracy.

The
result of next year’s General Election won’t be determined by you and me, or
anybody who votes in a “safe seat” – whether it’s safe for the Tories, Labour
or Plaid Cymru.

It will
be determined by the floating voters in a relative handful of marginal
constituencies. Which, at a generous estimate, adds up to 4pc of the British
electorate.

What
those 4pc decide will have a major impact on so much – not least whether the
NHS survives as anything like the life-saving, life-improving service we all
know and cherish.

On the
NHS, as on so much else, the present government has a cynical record of
twisting the figures – though they have some way to go to match the US
Republicans’ trashing of anything resembling proper health care.

But
that is another story – one you can expect me to return to another time. When I
do I shall aim to satisfy the Royal Statistical Society’s requirement to question, analyse and investigate the
issues that affect society at large.

Over the course of
my life I’ve been among the runners-up or on the short list for so many prizes
and awards that the law of averages says I should win this one.

Except that the law
of averages is a load of rubbish. If there really is such a thing, it surely states
that most people who quote averages don’t understand them.

I heard some
government flunkey the other day expressing outrage that “nearly half of all
schools are below average”. Well, yes.

Make them better
(assuming you actually have a proper way of rating them, which they don’t) and
the average will rise. Leaving something like half (maybe the same half, maybe
not) still below average.

And there’s another
story there too.

****

And speaking of the
misleading use of figures...

More than one paper
reported recently that a warm day in Britain was “twice as hot as Athens!”

Someone should
point out to them that 20 degrees Celsius is not twice as hot as 10 degrees –
merely twice as far above the freezing-point of water.

It may make it
clearer if it’s expressed in Fahrenheit. No one would imagine for a moment that
68 degrees was “twice as hot” as 50 degrees.

If any place on
Earth was actually twice as hot, in absolute terms, as any other, then either
one would be much too cold to support life or the other much too hot. Or both.

Between the
coldness of absolute zero (minus 273 degrees C) and, say, the sun’s surface temperature
(5,600 C), the range in which we can exist at all is really rather narrow.